You still need a bleeder resistor to avoid premature aging.
I have seen the carcasses of 2 GSB-201. Both had suffered violence of some
sort and been partly dismembered prior to viewing. I was not able to perform
an autopsy.
The original amp used 4 x 811A tubes. But, then some marketing guru realized
they could put 572 tubes in place of 811A tubes and call it good for 2 KW.
But, remember, Gonset was not known for building "built for stout, brick on the
key" amplifiers. In fact, they soon went out of business.
It has been a long time since I played with one, but I would assume that each
component is not rated for 2 KW, then evaluate yourself how much you wish to
push the safety envelope. Removing the choke will reduce the power rating of
the transformer even further.
The components were not designed for the higher voltage and not designed for
the higher power. Gonset pulled the envelope down - using the least expensive
component that would work. Why would they use a plate capacitor higher than
the rated plate voltage?
As I get older, I get more conservative. I might take an amp rated for 1500
watts and run it at 1200 watts. I would not take an amp originally rated at
1,000 watts and run it at 2,000 watts, but maybe I have simply gotten more
conservative after flying helicopters, where a part failure might mean
emergency landing, a lot of expenses or worse.
But, with an amplifier, the worse thing that can happen is a flash of light, a
kapow, then usually silence. Hey, that is not that bad, go for it.
Colin K7FM
-----Original Message-----
>From: KA9S - 2 <ka9s2@comcast.net>
>Sent: Mar 23, 2006 12:05 PM
>To: Jim Tonne <tonne@comcast.net>, AMPs <amps@contesting.com>
>Subject: Re: [Amps] Gonset GSB-201 Mods
>
>The paragraph above stated
>
>" I am getting a Gonset GSB-201 that has modifications. ........and the HV
>choke input filter choke is missing."
>
>There is no filter choke left in this amp. I can only configure it with the
>filter capacitors alone. The choke is gone. The orininal purpose of the 50K
>resistor was to draw enough current through the filter choke (which again is
>gone now) to keep the supply in regulation. If the supply no longer has a
>choke, I see no reason for the 50K resistor.
>
>- Jeff - KA9S
>
>----- Original Message -----
>From: "Jim Tonne" <tonne@comcast.net>
>To: "KA9S - 2" <ka9s2@comcast.net>; "AMPs" <amps@contesting.com>
>Sent: Thursday, March 23, 2006 11:04 AM
>Subject: Re: [Amps] Gonset GSB-201 Mods
>
>
>>
>> If that 50k resistor is the bleeder on the power supply,
>> * leave it alone * !!!
>>
>> > I had been thinking that changing the HV supply from
>> > choke input to capacitor input would boost the HV up
>> > to 2100 V and eliminate the need for the 50k 100W
>> > load resistor (it adds 45W of extra heat).
>>
>> - Jim WB6BLD
>>
>>
>
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